Mitochondrial dysfunction is a major cause of thromboinflammation and inflammatory cell death in critical illnesses

The significance of calcium ions in cerebral ischemia-reperfusion injury: mechanisms and intervention strategies

Cerebral ischemia-reperfusion injury (CIRI) represents a multifaceted pathological phenomenon characterized by an array of molecular and cellular mechanisms, which significantly contribute to neurological dysfunction. Evidence suggests that calcium ions play an indispensable role in this context, as abnormal elevations in calcium concentrations exacerbate neuronal injury and intensify functional deficits. These ions are integral not only for intracellular signaling pathways but also for various pathological processes, such as programmed cell death, inflammatory responses, and oxidative stress. This review article elucidates the physiological framework of calcium homeostasis and the precise mechanisms through which calcium ions influence CIRI. Moreover, it addresses potential intervention strategies, including calcium channel blockers, calmodulin (CaM) inhibitors, antioxidants, and anti-inflammatory agents. Despite the proposal of certain intervention strategies, their effectiveness and safety in clinical settings warrant further scrutiny. In conclusion, the article highlights the limitations of current research and anticipates future investigative trajectories, aiming to provide a theoretical foundation and reference for the development of more efficacious treatment modalities.

Impact of hyper- and hypothermia on cellular and whole-body physiology

The incidence of heat-related illnesses and heatstroke continues to rise amidst global warming. Hyperthermia triggers inflammation, coagulation, and progressive multiorgan dysfunction, and, at levels above 40 °C, can even lead to cell death. Blood cells, particularly granulocytes and platelets, are highly sensitive to heat, which promotes proinflammatory and procoagulant changes. Key factors in heatstroke pathophysiology involve mitochondrial thermal damage and excessive oxidative stress, which drive apoptosis and necrosis. While the kinetics of cellular damage from heat have been extensively studied, the mechanisms driving heat-induced organ damage and death are not yet fully understood. Converse to hyperthermia, hypothermia is generally protective, as seen in therapeutic hypothermia. However, accidental hypothermia presents another environmental threat due to arrhythmias, cardiac arrest, and coagulopathy. From a cellular physiology perspective, hypothermia generally supports mitochondrial homeostasis and enhances cell preservation, aiding whole-body recovery following resuscitation. This review summarizes recent findings on temperature-related cellular damage and preservation and suggests future research directions for understanding the tempo-physiologic axis.